Decline in the Use of Anthracyclines for Breast Cancer

Abstract

Purpose To determine the patterns of use of anthracycline- and taxane-based chemotherapy for breast cancer treatment. Methods Claims from a 5% national Medicare sample and from a nationally representative claims database (Marketscan) from 1998 to 2009 were used. Patients with International Classification of Diseases (ICD), ninth revision, codes indicating breast cancer, ICD and Common Procedural Terminology codes indicating breast surgery, and claims for chemotherapy between 3 months before and 12 months after surgery comprised the study cohort. Chemotherapy was classified as anthracycline-based or taxane-based, and the percentages of use were calculated. Piecewise regression models were used to identify the inflection points in the rates of chemotherapy use. The effect of patient characteristics on receiving different types of chemotherapy was estimated by multivariable logistic regression models. Results A total of 4,458 patients were included in the Medicare cohort and 30,422 in the private insurance c...